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Index clarification

kparthiApr 27 2016 — edited Apr 27 2016

Hi All ,

I am having clarification on how index are stored .

I keep on reading that B-tree unique index are stored in sorted order( default ascending )

Indexes can be unique or nonunique. Unique indexes guarantee that no two rows of a table have duplicate values in the key column or columns. For example, no two employees can have the same employee ID. Thus, in a unique index, one rowid exists for each data value. The data in the leaf blocks is sorted only by key.


Question:

User "A" insert into a table with 1,3,5( My understanding is B-tree index is created with Root Block--->Branch Block-->Leaf Block for storing 1,3,5 in aceding order )

User "B" insert into a table with 2,3,6

(

-- Now the questin is how the index are stored in asceding order

  --is there any operation happening inisde the b-tree index so that the Leaf block is rebuilded

  -- or is there any different way the leaf block is created

)



create table test_index (a number primary key );

desc desc test_index;

desc test_index

Name Null     Type 

---- -------- ------

A    NOT NULL NUMBER

INDEX_NAME                     UNIQUENESS

------------------------------ ----------

SYS_C00413788                  UNIQUE

-- User A tries to insert 1 ,3 , 5

insert into test_index values (1);

insert into test_index values (3);

insert into test_index values (5);

commit;

-- My understanding is B-tree index is created with Root Block--->Branch Block-->Leaf Block for storing 1,3,5 in aceding order

-- User B tries to insert 2 ,4 , 6

insert into test_index values (2);

insert into test_index values (4);

insert into test_index values (6);

commit;

-- Now the questin is how the index are stored in asceding order

  --is there any operation happening inisde the b-tree index so that the Leaf block is rebuilded

  -- or is there any different way the leaf block is created

Comments

843849
I'm very interested in your project.

I have a lot of experience using the avetana project, and would love to have a more advanced bluetooth library to work with.

The application I am interested in working on, is a web interface to a bluetooth hosting service, providing a "bluetooth hotspot" for people to share and download files, with one another etc.

Since JSP is my preferred web coding technique, this makes a lot of sense to me! Being able to start the service, scan for bluetooth devices and list them with a web interface would be a great application of your library.

Cheers
Greg
843849
hi, im very interested in your project but im new to java. do you have any example in netbeans or can help me?
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Locked on May 25 2016
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